diff --git a/paste/views.py b/paste/views.py
index 46a4b5a..28632a6 100644
--- a/paste/views.py
+++ b/paste/views.py
@@ -53,7 +53,7 @@ class PasteView(View):
         paste = get_object_or_404(Paste, slug=path)
         paste.incr_viewcount()
 
-        if "html" in request.headers["accept"]:
+        if "html" in request.headers.get("accept", "html"):
             return HttpResponse(paste_to_html(paste.filename, paste.content))
         else:
             return HttpResponse(paste.content, content_type="text/plain")
@@ -124,7 +124,7 @@ class ListView(View):
                 "viewcount",
             ),
         )
-        if "html" in request.headers["accept"]:
+        if "html" in request.headers.get("accept", "html"):
             return HttpResponse(
                 loader.render_to_string(
                     "paste/show-markdown.html", {"highlighted": markdown_to_html(table)}